Conventionally, highly indicative or decorative sheets intended for displaying indoor or outdoor information, advertisements, or guidance are often used on wall or floor surfaces. Taking outdoor places as examples, such display sheets are attached to floor surfaces of roads, viaducts, platforms, building rooftops, parking lots, and the like. The utilization of these display sheets in various spaces as information media such as advertisements, guide signs, and information is frequently observed in our daily lives. When these display sheets are attached to outdoor floor surfaces as described above, they are required to retain their indicativeness or decorativeness even after exposure to a heavy traffic of pedestrians on the floor surfaces. For this reason, the display sheets are typically coated with a transparent protective film having mechanical durability or strength, such as wear resistance or damage resistance, on their printed surfaces printed with information such as advertisements, or guide or information signs, in order to retain desired strengths and appearances. For this purpose, protective films having not only durability but also contamination resistance have been previously proposed (see, for example, Patent Document 1). Methods for coating a printed surface printed with information, such as information or guide signs, with a protective layer have also been proposed (see, for example, Patent Document 2). These protective films or layers are taught to enhance the mechanical durability, wear resistance, and damage resistance.
Further, display sheets attached to floor surfaces are required to have surface-slip resistance as a capability different from capabilities required in display sheets intended for signboards or wall surfaces and not for floor surfaces. That is, display sheets attached to floor surfaces must allow pedestrians to safely travel thereon. Known methods for enhancing the slip resistance are display sheets of a type wherein inorganic particles that form projections on a sheet surface are dispersed and fixed (see, for example, Patent Document 3); and display sheets of a type having a specific surface shape by the application of roughness treatment to the sheet surface (see, for example, Patent Document 4). Display sheets of the former type have been obtained by extending the idea of providing a protective layer on a printed surface. Moreover, the hard particles added, rather than a synthetic resin that is a principal component used in the protective layer, provide a non-slip function. Display sheets of the latter type also require the provision of a protective layer as a precondition, wherein slip resistance is achieved by processing the surface of a principal material that forms the surface of the protective layer, i.e., a synthetic resin or the like, into a specific shape, thereby ensuring transparency as well.    Patent Document 1: Japanese Unexamined Patent Publication No. 1996-118553 (the claims; FIG. 1)    Patent Document 2: Japanese Unexamined Patent Publication No. 1999-10823 (the claims; FIG. 1)    Patent Document 3: Japanese Unexamined Patent Publication No. 1990-144461 (the claims)    Patent Document 4: Japanese Unexamined Patent Publication No. 2003-39582 (the claims; FIGS. 1 and 2)